Before you proceed, you need InTouchApp installed on your phone.
To change your InTouch username, please follow the below steps:
Step 1 - Open InTouchApp on your phone.
Step 2 - Click on your profile on the top center at the screen.
Step 3 - Click on Settings at the top right corner.
Step 4 - Click on Profile (under Manager your account)
Step 5 - Click on Change beside the Username.
Step 6 - Enter your new username and check the availability. Once done, click on the Green Tickon the right and it's changed.